The Croydon South Parliamentary selection continues, but without Boris Johnson – which raises the question of why he isn’t in it (or in other contests), and whether or not he should be. There is one very good reason for him not to stand for the Commons in 2015; if he has already decided to fight a third election for the London Mayoralty. He is a successful Mayor and a global figurehead for the capital, so there is absolutely no reason why he shouldn’t do so. If any Conservative can win a third election running in what is at heart a Labour city, it’s Boris. But since his ambitions are evidently larger than London, it’s impossible to believe that he has settled on standing again.

That they are bigger isn’t in doubt, as his interview in a recent Michael Cockerell documentary confirmed. He said that he would like to “have a crack” at being Prime Minister “‘if the ball came loose from the back of a scrum”. Why, then, has he not declared that he wants to re-join the team on the playing fields of Westminster? The apparent answer is that he would were he confident that there will be a leadership election after 2015, but that since he isn’t, he won’t. He is said not to wish to serve under David Cameron. Perhaps he believes that he wouldn’t be treated fairly by a leadership with which he has tense relations (though less with the Prime Minister than the Chancellor), and that to soldier on as a Minister until 2020, only to find some younger face poised to succeed Cameron as Conservative leader, is not a pleasing prospect.

I can understand why Boris might not be convulsed with enthusiasm at the prospect of being greeted by a triumphant Cameron, after an election that sees the latter returned to Downing Street and the former to the Commons, more or less as follows: “Boris! Come in! Great to see you! As the senior figure in local government until very recently, you’re just the man for CLG!” Or: “Boris! Just the man! Have a seat! As Britain’s most eloquent advocate for Crossrail, you’re just the man for Transport!” But while such reservations would be understandable, would they also be reasonable? Being a Cabinet member isn’t a bad gig, even in the most unglamorous department. Helping to sort out bin collections and T-junctions is all part of public service, whether it marks out a route to Downing Street or not. Were the Mayor less popular in the Party and elsewhere than he is, these points would already have been made, and forcefully.

All in all, a return to the Commons may have a downside for Boris, but it would be all upside for everyone else – in the Conservative Party, at any rate. If it is in government after the next election, he deserves the chance to run a department. (The leadership may distrust him, but surely couldn’t, in such circumstances, keep him out of Cabinet.) And if it is not in government, it deserves the chance to be able to consider him as a candidate for the leadership. I appreciate that simultaneously being London’s Mayor and serving as Conservative leader are apparently irreconcilable (though there is certainly no difficulty about being the Mayor while also sitting as an MP). But suggestions that the Party could, after a 2015 defeat, wait for a new leader until after Boris stands down as Mayor in 2016 are also deeply problematic. A leadership election without him could all too easily be portrayed, both by his admirers and the Party’s opponents, as having no legitimacy: of playing Henry IV without Falstaff or, to be more exact, Prince Hal – the wayward roisterer who, by grace of state, is transformed into “this star of England”. Boris should stand for the Commons in 2015.